The present invention relates to an intravaginal device for electrically stimulating muscles and nerves defining and surrounding the intravaginal cavity and/or for sensing electrical activity of said muscles, and, more particularly, to a device and system utilizing same which are useful in preventing or treating urinary incontinence in women.
Urinary Incontinence
Urinary incontinence is characterized by the involuntary loss of urine in individuals. Urinary incontinence is typically brought on sphincter dysfunction or by weakening of the pelvic floor support musculature, which weakening leads to a xe2x80x9cdroppedxe2x80x9d bladder, a condition often termed as xe2x80x9ccystocelexe2x80x9d.
Urinary incontinence affects approximately 13 million people in the United States alone, 85% of them women. Urinary incontinence can be caused by physical stress (stress incontinence) typically brought on by heavy object lifting, coughing, laughing or sneezing, an overactive bladder (typically referred to as urge incontinence) or by an uncontrollable slow leak which is termed over flow incontinence, and which is often experienced when complete bladder emptying can not be achieved by an individual. Additional but less common types of urinary incontinence include functional incontinence and unconscious or reflex incontinence.
Of the above causes for urinary incontinence, stress incontinence and urge incontinence are considered the most prevalent. In such cases, urine loss occurs when the intravesicle pressure (i.e. pressure within the urinary bladder) exceeds, even by a small amount of pressure, the maximum urethral pressure (i.e., pressure in the urethra to maintain closure). While the problem of stress incontinence occurs in both men and women, it predominantly occurs in women of childbearing age and beyond; the frequency of incontinence in women is approximately four times that of men. Less than one-third of women with moderate to severe incontinence are treated for the problem. While 25 to 41% of all women suffer some form of incontinence, 6 to 8% are troubled by the problem to the extent that they must wear diapers or sanitary napkins constantly.
There are several exercise programs, devices, and surgical procedures which can be used to alleviate urinary incontinence.
The xe2x80x9ckegelsxe2x80x9d exercise program is among the most basic and simple non surgical alternative for treating urinary incontinence. Such an exercise program helps to strengthen the pelvic floor muscles to thereby treat urinary incontinence. Unfortunately, many women do not perform the xe2x80x9ckegelsxe2x80x9d exercises correctly, and as such, in most cases, no significant improvement or alleviation is achieved. In addition, recent studies have shown that the xe2x80x9ckegelsxe2x80x9d exercise program is only effective in cases of mild to moderate urinary incontinence.
Other non surgical alternatives include diapers which simply absorb the urine involuntarily voided and as such do not alleviate the problem of incontinence. Such diapers also suffer from hygienic and aesthetic drawbacks, leakage occurs frequently, and there is no control over the voiding of urine.
A number of devices and plugs which are designed at preventing urine loss and which overcome such limitations associated with diapers have also been described in the prior art.
U.S. Pat. No. 4,457,299 to Corewell teaches an internally prestressed capsule device which is inserted into the urethra in order to aid in urinary incontinence.
U.S. Pat. No. 5,090,424 to Simon et al. describes a flexible urethral plug, designed for blocking involuntary urine flow through the urethra and assisting the natural function of the sphincter in closing the urethra.
Although such devices are functional in preventing accidental voiding of urine, they cannot be utilized to treat and/or alleviate the causes of urinary incontinence.
As such, a number of devices for treating urinary incontinence, which devices function in electrically stimulating the patient""s musculature and/or monitoring muscle feedback have been described.
Electro-stimulation has been found to be effective in increasing muscle strength while biofeedback monitoring of muscular activity is valuable in assessing muscle activity and thus promoting correct pelvic floor muscle control by the patient.
U.S. Pat. No. 4,396,019 to Perry, Jr., teaches the use of an electrode-carrying insert which functions in providing the patient with feedback on muscle activity and as such enables the patient to exercise self control over the musculature contributing to urinary incontinence.
U.S. Pat. No. 4,881,526 to Johnson teaches of an intravaginal electrode and controller for preventing female urinary incontinence. The electrode includes an elongated and generally cylindrical carrier having a rounded tip, an extended lip, and a neck of reduced diameter. Motor receptor electrical stimulation signals received from the controller are coupled to the motor electrodes and directly stimulate pelvic floor musculature.
The rigid, non-yielding structure, of the above described electrode carrying devices presents several disadvantages. Since contact between a wall of the intrabody cavity and an electrode of such devices is of utmost importance for efficient muscle activation, such devices must be fabricated in a variety of sizes to fit a variety of anatomical builds. In addition, the rigid construction of such devices interferes with the physiological movement of an exercising vaginal muscle. Furthermore, the rigidity of the device greatly increases patient discomfort.
To overcome these limitations, U.S. Pat. No. 5,662,699 to Hamedi, teaches of a device which includes a flexible airtight sheath with a resilient skeleton and outer conductive bands which is collapsed by vacuum and inserted into the body cavity. When inflated within the cavity, the skeleton expands the sheath and forces the conductive bands against the body cavity wall thus ensuring optimal contact.
This device is limited to recording muscle activity, no description is provided for its ability to induce muscle stimulation. In addition, although the use of such configuration overcomes the limitations inherent to rigid electrode carrying devices, the need for an inflating/deflating mechanism greatly complicates the fabrication and application of such a device and if air leakage should occur, also its reliability in interpretation of the results.
There is thus a widely recognized need for, and it would be highly advantageous to have, an intravaginal device capable of electrically stimulating, and/or recording the activity of, the musculature/nervature defining and surrounding the intravaginal cavity and yet devoid of the above mentioned limitations of prior art designs.
According to one aspect of the present invention there is provided a device for stimulating muscles and nerves defining and surrounding an intravaginal cavity of an individual, the device comprising (a) a body having memory properties such that when the body is contracted and positioned within an intravaginal cavity of the individual the body self expands to conform to a contour of the intravaginal cavity; and (b) at least one pair of electrodes being attached to an exterior surface of the body, such that when the body is positioned within the intravaginal cavity, each electrode of the at least one pair of electrodes is biased against a wall of the intravaginal cavity to thereby maintain electrical contact with the wall. The electrical current providable from the at least one pair of electrodes serves for electrically stimulating muscles and nerves defining and surrounding the intravaginal cavity.
According to further features in preferred embodiments of the invention described below, the device further comprising a power and control unit being for providing the electrical current to the at least one pair of electrodes, the power and control unit being attachable to connectors being in electrical communication with the at least one pair of electrodes.
According to still further features in the described preferred embodiments the connectors are positioned on a region of the body such that when the body is positioned within the intravaginal cavity and attached to the power and control unit, the power and control unit is positioned outside of the intravaginal cavity.
According to still further features in the described preferred embodiments the device further comprising at least one sensor attached to the body, such that when the body is positioned within the intravaginal cavity, the at least one sensor is capable of sensing muscle activity of the muscles and nerves defining and surrounding the intravaginal cavity, so as to serve for a loop feedback or biofeedback.
According to still further features in the described preferred embodiments the at least one sensor attached to the body is a pressure sensor or an electrical activity sensor.
According to still further features in the described preferred embodiments the at least one sensor attached to the body further includes a transmitter and an internal power source.
According to still further features in the described preferred embodiments the transmitter serves for transmitting a signal receivable outside the body, the signal including data pertaining to the muscle activity sensed by the at least one sensor.
According to another aspect of the present invention there is provided a system for stimulating muscles and nerves defining and surrounding an intravaginal cavity of an individual, the system comprising: (a) an intravaginal positionable device assembly including: (i) a body having memory properties such that when the body is contracted and positioned within the intravaginal cavity of the individual the body self expands to conform to a contour of the intravaginal cavity; and (ii) at least one pair of electrodes being attached to an exterior surface of the body such that when the body is positioned within the intravaginal cavity, each electrode of the at least one pair of electrodes is biased against a wall of the intravaginal cavity to thereby maintain electrical contact with the intravaginal cavity wall, the electrical current providable from the at least one pair of electrodes serves for electrically stimulating muscles and nerves defining and surrounding the intravaginal cavity; and (iii) a power and control unit being detachably attached to the body and being for providing electrical current to the at least one pair of electrodes; and (iv) at least one sensor attached to the body, such that when the body is positioned with in the intravaginal cavity, the at least one sensor is capable of sensing muscle activity of the muscles and nerves defining and surrounding the intravaginal cavity; and (v) a transmitter being for transmitting a signal receivable outside the body, the signal including data pertaining to the muscle activity sensed by the at least one sensor; and (b) an extracorporeal monitoring unit being for processing the signal received from the transmitter to thereby determine duration or intensity of the electrical current provided to the at least one pair of electrodes from the power and control unit.
According to yet another aspect of the present invention there is provided a method of stimulating muscles and nerves defining and surrounding an intravaginal cavity of an individual, the method comprising the steps of: (a) positioning an intravaginal device within the intravaginal cavity of the individual, the intravaginal device including: (i) a body having memory properties such that when the body is contracted and positioned within an intravaginal cavity of the individual the body self expands to conform to a contour of the intravaginal cavity; and (ii) at least one pair of electrodes being attached to an exterior surface of the body such that when the body is positioned within the intravaginal cavity, each electrode of the at least one pair of electrodes is biased against a wall of the intravaginal cavity to thereby maintain electrical contact with the wall, wherein the electrical current providable from the at least one pair of electrodes serves for electrically stimulating muscles and nerves defining and surrounding the intravaginal cavity; and (b) providing the electrical current of a predetermined intensity and/or duration to the at least one pair of electrodes attached to the exterior surface of the body to thereby stimulate muscles and nerves defining and surrounding the intravaginal cavity of the individual.
According to still further features in the described preferred embodiments the system serves for treating or preventing urinary incontinence in the individual.
According to still further features in the described preferred embodiments the body is constructed of an elastic material selected from the group consisting of silicon, rubber and latex. Other flexible materials are also envisaged.
According to still further features in the described preferred embodiments a width of the body when relaxed is at least 1.3-1.5 times larger than the width of the body when fully contracted.
According to still further features in the described preferred embodiments a length of the body when relaxed is 1.3-1.7, preferable 1.5, times shorter than the length of the body when fully contracted.
According to still further features in the described preferred embodiments the at least one pair of electrodes include a conductive material selected from the group consisting of gold and platinum.
According to still further features in the described preferred embodiments the at least one sensor attached to the body is a pressure sensor or an electrical activity sensor.
According to still further features in the described preferred embodiments the power and control unit includes a receiver for receiving command signal from the extracorporeal unit, the command signals serving for modulating the duration or the intensity of the electrical current provided to the at least one pair of electrodes from the power and control unit.
According to still further features in the described preferred embodiments the body defines a substantially rounded diamond shaped frame when relaxed.
According to still further features in the described preferred embodiments stimulation of the muscles and nerves defining and surrounding the intravaginal cavity serves for treatment or prevention of urinary incontinence in the individual.
According to another aspect of the present invention there is provided a device for sensing electrical activity of muscles defining and surrounding an intravaginal cavity of an individual, the device comprising (a) a body having memory properties such that when the body is contracted and positioned within an intravaginal cavity of the individual the body self expands to conform to a contour of the intravaginal cavity; and (b) at least one pair of electrodes being attached to an exterior surface of the body such that when the body is positioned within the intravaginal cavity, each electrode of the at least one pair of electrodes is biased against a wall of the intravaginal cavity to thereby maintain electrical contact with the wall.
The present invention successfully addresses the shortcomings of the presently known configurations by providing an intravaginal device for stimulating the muscles and nerves defining and surrounding the intravaginal cavity and/or for sensing electrical activity of said muscles, which device can be fitted to a wide range of anatomical builds, is easy to position while remaining at the desired location and orientation within the intravaginal cavity, and yet minimizes patient discomfort when utilized.